增强混凝土梁的结构性能改进 通过应变硬化水泥复合层增强混凝土梁的结构性能
M Iqbal Khan1, Sardar Umer Sial1, Yassir M Abbas1
1Department of Civil Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia.
Materials (Basel, Switzerland)
|July 29, 2023
概括
应变硬化混凝土复合材料 (SHCC) 层显著提高了钢筋混凝土 (RC) 梁的承载能力和裂纹控制. 30%的SHCC层厚度在提高曲性能和柔性方面被证明是最有效的.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 结构工程 结构工程
背景情况:
- 应变硬化混凝土复合材料 (SHCC) 提供优越的柔性和耐用性.
- SHCCs在裂控制和增强结构成员承载能力方面具有潜在的应用.
- 钢筋混凝土 (RC) 梁可以从材料增强中获益,以提高性能.
研究的目的:
- 调查SHCC层在提高预制RC梁的承载能力方面的有效性.
- 评估不同厚度的SHCC层对RC梁的屈曲性能和裂纹行为的影响.
- 开发和验证一种分析方法,用于预测SHCC层RC梁的屈曲反应.
主要方法:
- 在RC梁的底部张力区域中造不同厚度的SHCC层 (0%,15%,30%,45%的截面高度).
- 在实验室尺度梁上进行四点曲试验.
- 采用分析方法来预测复合梁的屈曲反应.
主要成果:
- 与控制RC光束相比,SHCC层的RC光束表现出更好的曲性能.
- 具有30%SHCC层厚度的RC光束在强度,延展性和裂纹控制方面表现出最显著的改进.
- 分析方法准确地预测了瞬间容量,与测量值的平均差异小于10%.
结论:
- 将SHCC叠加在RC梁上是一种有效的改装策略,以提高结构性能.
- 优化SHCC层厚度对于最大化益处至关重要,在本研究中30%显示最佳结果.
- 开发的分析模型提供了一个可靠的工具,用于预测SHCC增强的RC光束的行为.
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